/*
** $Id: ldo.h,v 2.29 2015/12/21 13:02:14 roberto Exp $
** Stack and Call structure of Lua
** See Copyright Notice in lua.h
*/

#ifndef ldo_h
#define ldo_h


#include "lobject.h"
#include "lstate.h"
#include "lzio.h"


/*
** Macro to check stack size and grow stack if needed.  Parameters
** 'pre'/'pos' allow the macro to preserve a pointer into the
** stack across reallocations, doing the work only when needed.
** 'condmovestack' is used in heavy tests to force a stack reallocation
** at every check.
*/
#define luaD_checkstackaux(L,n,pre,pos)  \
    if (L->stack_last - L->top <= (n)) \
      { pre; luaD_growstack(L, n); pos; } else { condmovestack(L,pre,pos); }

/* In general, 'pre'/'pos' are empty (nothing to save) */
#define luaD_checkstack(L,n)    luaD_checkstackaux(L,n,(void)0,(void)0)



#define savestack(L,p)      ((char *)(p) - (char *)L->stack)
#define restorestack(L,n)   ((TValue *)((char *)L->stack + (n)))


/* type of protected functions, to be ran by 'runprotected' */
typedef void ( *Pfunc )( lua_State* L, void* ud );

LUAI_FUNC int luaD_protectedparser( lua_State* L, ZIO* z, const char* name,
                                    const char* mode );
LUAI_FUNC void luaD_hook( lua_State* L, int event, int line );
LUAI_FUNC int luaD_precall( lua_State* L, StkId func, int nresults );
LUAI_FUNC void luaD_call( lua_State* L, StkId func, int nResults );
LUAI_FUNC void luaD_callnoyield( lua_State* L, StkId func, int nResults );
LUAI_FUNC int luaD_pcall( lua_State* L, Pfunc func, void* u,
                          ptrdiff_t oldtop, ptrdiff_t ef );
LUAI_FUNC int luaD_poscall( lua_State* L, CallInfo* ci, StkId firstResult,
                            int nres );
LUAI_FUNC void luaD_reallocstack( lua_State* L, int newsize );
LUAI_FUNC void luaD_growstack( lua_State* L, int n );
LUAI_FUNC void luaD_shrinkstack( lua_State* L );
LUAI_FUNC void luaD_inctop( lua_State* L );

LUAI_FUNC l_noret luaD_throw( lua_State* L, int errcode );
LUAI_FUNC int luaD_rawrunprotected( lua_State* L, Pfunc f, void* ud );

#endif

